SUBROUTINE initracer()

      use comgeomfi_h
      use aerosol_mod
      IMPLICIT NONE
c=======================================================================
c   subject:
c   --------
c   Initialization related to tracer 
c   (transported dust, water, chemical species, ice...)
c
c   Name of the tracer
c
c   Test of dimension :
c   Initialize COMMON tracer in tracer.h, using tracer names provided
c   by the dynamics in "advtrac.h"
c
c   author: F.Forget
c   ------
c            Ehouarn Millour (oct. 2008) identify tracers by their names
c            Tanguy Bertrand (oct. 2014) Adaptation Pluto
c            Tanguy Bertrand (dec. 2014) Adding tracers for haze 
c                                            -precurseur
c                                            -haze 
c=======================================================================


#include "dimensions.h"
#include "dimphys.h"
#include "comcstfi.h"
#include "callkeys.h"
#include "tracer.h"
#include "advtrac.h"
#include "fisice.h"
#include "surfdat.h"

!      real qsurf(ngridmx,nqmx)       ! tracer on surface (e.g.  kg.m-2)
      character(len=20) :: txt ! to store some text
      integer iq,ig,count,i
      real r0_lift , reff_lift, rho_haze
      integer nqhaze(nqmx)               ! to store haze tracers
!      logical :: oldnames ! =.true. if old tracer naming convention (q01,...)
      integer ia, block
      CHARACTER(LEN=20) :: tracername ! to temporarily store text

c-----------------------------------------------------------------------
c  radius(nqmx)      ! aerosol particle radius (m)
c  rho_q(nqmx)       ! tracer densities (kg.m-3)
c  rho_ch4_ice           ! ch4 ice density
c  rho_co_ice           ! co ice density
c  varian            ! Characteristic variance of log-normal distribution
c-----------------------------------------------------------------------

! Initialization: get tracer names from the dynamics and check if we are
!                 using 'old' tracer convention ('q01',q02',...)
!                 or new convention (full tracer names)

       ! copy tracer names from dynamics
        do iq=1,nqmx
          noms(iq)=tnom(iq)
        enddo

        print*,'initracer : number of tracers nqmx=',nqmx
      ! Identify tracers by their names: (and set corresponding values of mmol)
      ! 0. initialize tracer indexes to zero:
      ! NB: igcm_* indexes are commons in 'tracer.h'
      igcm_n2=0
      igcm_ch4_gas=0
      igcm_ch4_ice=0
      igcm_prec_haze=0
      igcm_co_gas=0
      igcm_co_ice=0

      nqhaze(:)=0
      i=0
      DO iq=1,nqmx
         txt=noms(iq)
         IF (txt(1:4).eq."haze") THEN
            i=i+1
            nqhaze(i)=iq
         ENDIF
      ENDDO
      if ((haze.or.fasthaze).and.i==0) then
         print*, 'Haze active but no haze tracer in traceur.def'
         stop
      endif
      igcm_haze=0
      igcm_haze10=0
      igcm_haze30=0
      igcm_haze50=0
      igcm_haze100=0

!     Eddy diffusion tracers 
      igcm_eddy1e6=0
      igcm_eddy1e7=0
      igcm_eddy5e7=0
      igcm_eddy1e8=0
      igcm_eddy5e8=0
      write(*,*) 'initracer: noms() ', noms

c     Radius and densities
      rho_n2=1000        ! n2 ice
      rho_ch4_ice=520.       ! rho ch4 ice
      rho_co_ice=520.       ! rho ch4 ice
      rho_haze=800.     ! haze
      ! first initialization 
      call zerophys(nqmx,rho_q)
      call zerophys(nqmx,radius)

      ! find tracers
      count=0
      do iq=1,nqmx
        if (noms(iq).eq."n2") then
          igcm_n2=iq
          mmol(igcm_n2)=28.
          count=count+1
          write(*,*) 'Tracer ',count,' = n2'
        endif
        if (noms(iq).eq."ch4_gas") then
          igcm_ch4_gas=iq
          mmol(igcm_ch4_gas)=16.
          count=count+1
          write(*,*) 'Tracer ',count,' = ch4 gas'
        endif
        if (noms(iq).eq."ch4_ice") then
          igcm_ch4_ice=iq
          mmol(igcm_ch4_ice)=16.
          radius(iq)=3.e-6
          rho_q(iq)=rho_ch4_ice
          count=count+1
          write(*,*) 'Tracer ',count,' = ch4 ice'
        endif
        if (noms(iq).eq."co_gas") then
          igcm_co_gas=iq
          mmol(igcm_co_gas)=28.
          count=count+1
          write(*,*) 'Tracer ',count,' = co gas'
        endif
        if (noms(iq).eq."co_ice") then
          igcm_co_ice=iq
          mmol(igcm_co_ice)=28.
          radius(iq)=3.e-6
          rho_q(iq)=rho_co_ice
          count=count+1
          write(*,*) 'Tracer ',count,' = co ice'
        endif
        if (noms(iq).eq."prec_haze") then
          igcm_prec_haze=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = prec haze'
        endif
        if (noms(iq).eq."haze") then
          igcm_haze=iq
          count=count+1
          radius(iq)=rad_haze
          rho_q(iq)=rho_haze
          write(*,*) 'Tracer ',count,' = haze'
        endif
        if (noms(iq).eq."haze10") then
          igcm_haze10=iq
          count=count+1
          radius(iq)=10.e-9
          rho_q(iq)=rho_haze
          write(*,*) 'Tracer ',count,' = haze10'
        endif
        if (noms(iq).eq."haze30") then
          igcm_haze30=iq
          count=count+1
          radius(iq)=30.e-9
          rho_q(iq)=rho_haze
          write(*,*) 'Tracer ',count,' = haze30'
        endif
        if (noms(iq).eq."haze50") then
          igcm_haze50=iq
          count=count+1
          radius(iq)=50.e-9
          rho_q(iq)=rho_haze
          write(*,*) 'Tracer ',count,' = haze50'
        endif
        if (noms(iq).eq."haze100") then
          igcm_haze100=iq
          count=count+1
          radius(iq)=100.e-9
          rho_q(iq)=rho_haze
          write(*,*) 'Tracer ',count,' = haze100'
        endif
!       Eddy diffusion tracers
        if (noms(iq).eq."eddy1e6") then
          igcm_eddy1e6=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = eddy1e6'
        endif
        if (noms(iq).eq."eddy1e7") then
          igcm_eddy1e7=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = eddy1e7'
        endif
        if (noms(iq).eq."eddy5e7") then
          igcm_eddy5e7=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = eddy5e7'
        endif
        if (noms(iq).eq."eddy1e8") then
          igcm_eddy1e8=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = eddy1e8'
        endif
        if (noms(iq).eq."eddy5e8") then
          igcm_eddy5e8=iq
          count=count+1
          write(*,*) 'Tracer ',count,' = eddy5e8'
        endif
      enddo ! of do iq=1,nqmx
      
      ! check that we identified all tracers:
      if (count.ne.nqmx) then
        write(*,*) "initracer: found only ",count," tracers"
        write(*,*) "               expected ",nqmx
        do iq=1,count
          write(*,*)'      ',iq,' ',trim(noms(iq))
        enddo
        stop
      else
        write(*,*) "initracer: found all expected tracers, namely:"
        do iq=1,nqmx
          write(*,*)'      ',iq,' ',trim(noms(iq))
        enddo
      endif

c------------------------------------------------------------
c     Initialisation tracers ....
c------------------------------------------------------------

c     Other initializations
c     ------------------------------

c     Latent heat :
      lw_co=274000.
      lw_ch4=586700.
      lw_n2=2.5e5

c     HAZE: 
      if (haze) then
         ! the sedimentation radius remains radius(igcm_haze)
         if (fractal) then
            nmono=nb_monomer
         else
            nmono=1
         endif  

         ia=0
         if (aerohaze) then
            ia=ia+1
            iaero_haze=ia
            write(*,*) '--- number of haze aerosol = ', iaero_haze

            block=0  ! Only one type of haze is active : the first one set in traceur.def
            do iq=1,nqmx
              tracername=noms(iq)
              write(*,*) "--> tracername ",iq,'/',nqmx,' = ',tracername
              if (tracername(1:4).eq."haze".and.block.eq.0) then
                i_haze=iq
                block=1
                write(*,*) "i_haze=",i_haze
                write(*,*) "Careful: if you set many haze traceurs in 
     & traceur.def,only ",tracername," will be radiatively active 
     & (first one in traceur.def)"
              endif
            enddo
         endif
      endif

c     Output for records:
c     ~~~~~~~~~~~~~~~~~~
      write(*,*)
      Write(*,*) '******** initracer :  parameters :'
      write(*,*) 'radius  = ', radius
      write(*,*) 'density = ', rho_q
      write(*,*)
      write(*,*) 'monomers = ', nmono

      end